The invention relates to an attachment buckle comprising a base provided with a hook for attaching a retaining ring, and control means able to occupy a locking position and a releasing position to respectively secure and release the retaining ring on and from the latching hook, the control means comprising two locking elements independent from one another and both having a stop and a control button.
The fixing buckle is connected to a strap of a belt or to a harness for climbing, caving or for working at a height. For safety reasons, any untimely opening of the buckle has to be impossible.